Improvement in sewing-machines



- M. e. WILDER, on MERIDEN, connnoricur.

' IMPROVEMENT lN SEWING-MACHINES.

Specification forming part of Letters Patent No. 32,323, dated May 14,1861.

To all whom "it may concern:

Be it known that I, M. G. WILDER, of Meriden, in the county of New Havenand State of Connecticut, have invented certain new and usefiilImprovementsin Sewing-Machines; and I do hereby declare that thefollowing is a full, clear, and exact description of my said invention,reference being had to the accompanying drawings, in which- Figure 1represents a side elevation of a sewing machi-ne constructed accordingto the principles of my invention, a portion of the bed-plate and thespool and tension for the lower thread being removed to permit theremainder of the machine to be seen more clearly. Fig. 2 represents afront elevation of the machine with the portions to the left of the lineas w of Fig. I removed. Figs. 3.and 4 represent sectional viewsofcertain parts of the machine in two different positions, and Fig. 5 isa face view of a part of the machine.

My invention has reference to that class of sewing-machines which makewhat is known as the double-thread loop-stitch and it consists incertain combinations of mechanical devices by means of which theoperation of the looper thatcarries the under or looping thread isrendered more certain, while at the same time the construction of theparts is such that the machine can be made at a low cost.

The'first part of my invention has reference to the lateral movement ofthe looper, by which.

it is caused to shift from one side of the needle to the other, so as tohold a loop of the thread it carries open for the entrance of the needleafter it has entered the loop of needlethread. This part of my inventionconsists incombining the rock-shaft of the looper with a pitman, which Iprefer to be that of the crank that operates the needle, by-means ofblocks or plates fitted with wedge formed or inclined projections insuch manner that the transverse ascending movement of the pitman causesthe looper-shaft to rock in one direction, and the transverse descendingmovement of the pitman causes it to rockin the opposite direction.

The second part of my invention has reference to the longitudinalmovement of the looper; and its objectis to cause a looper which isdriven by a crank-pin and by a pitman that is parallel, or thereabout,(when in its mean position,) to the looper to pass by the needle andseize the loop of needle-thread sooner than it otherwise would, and toback out of the loop of needle-thread seized by it sooner than itotherwise would. This part of my invention consists in combining theshaft of the looper with the pitman of the crank-pin by means of a pinand slotted cam-plate, the slot of which is composed of two parts, bothof which extend transversely to the pitman, but are not located in thesame perpendicular line tothe length of the pitman, the one part beingin advance ofa perpendicular line drawn midway between the two when thepitman is moving'in one direction, and the other part being in advanceof the same perpendicular line when the pitman is moving in the oppositedirection, and each part acting in succession with the pin. This part ofmy invention enables me to operate the looper by the same crank-pin andpitman that operates the needle, and nevertheless cause the looper toenter the loop ot'needle thread soon enough after its formation toseizeit with certainty, and also to back out of and release the saidloop before the needle has completed its descending movement for thenext stitch; thus permitting the stitch to be pulled tight hy thedescent of the needle.

The third part of my inventionconsists in the combination of thecrank-pin and connecting roil that operates the needle-arm with theshaft of the loo per by means of plates fitted with the wedge -formedprojections, can] -groove, and pin before mentioned, so that both partsof my invention are combined together in the same machine, whereby I amenabled to derive both the before-described longitudinal and lateralmovements of the looper from the same crank-pin and pitman that operatethe needle.

The object of the fourth part of my invention is to facilitate thethreading of the looper; and it consists in combining alooper having aneye at'its point with a hook near its butt for retaining the thread'bythe side of the looper, in place of a second eye. This improvementrenders it only necessary to pass the second thread through one eye uponthe looperinstead of through two, and facilitates the threading of thelooper, as the thread can he slipped over the hook with much greaterease than it can be passed through a second eye. 7 p

The sewing-machine represented in tho accompanying drawings embodies myinvention in the best form that I have devised. In this machine theneedle ais secured to a needlebar, B, which is held in guides secured toa line with each other, and are connected by an fixed arm, 0, thatprojects from the bed-plate A of the machine, and is caused to ascendand descend by means of a bent lever or needlearm, D,pivoted to thefixed arm 0. The lower end of the needle-arm D is connected by a pitingshal'tm also operates the feed-bar a by means of a face-cam, b, and'anedge cam,d, in the usual manner.

The looper 9, that carries the lower or looping thread, is secured to anarm, h, that projeGILS upward from a rock-shaft, [,whi'ch forms thelooper-stock. This looper has an eye at its point for carrying thesecond thread, and at its butt there is a hook, 21, around which thesecond thread is passed, and which holds this thread alongside of thelooper. The rockshaft I is supported in a long hearing or stationarysleeve, J, that is secured to the bedplate, and permits the rock-shaftIboth to more to and fro longitudinally and to rock. Thehinderextremityot' the rock-shaftis fitted with a cross-block orhead-plate, K, having two pro- I jections, c 0, Figs. 3and 4, at themargins of one ot'its faces, and the parts of these projections that arenearest to each other are inclined or wedge formed. The face of thecrossblock which has the projections bears against the face of a plate,L, that is secured to and projects upward from the pitman E, that drivesthe needle-arm. The margins of that face of the pitman' plate L which isadjacent to the head-plate Kot' the looper-shaft are fitted with1rojections'ii,F1gs.3 and 4,and the parts of these projections that arenearest to each other are inclined or wedge-formed. From thisconstruction Of-thehead-plate of the looper and of the pitman-plate itfollows that as the pitman is caused by the rotation of its crank-pin torise above and descend below its mean position, the lower and upperwedge-formed projections ofthe pitman-rod plate L are caused to actalternately upon the corresponding projections ofthe cross-plate K ofthe loopershaft, and this shaft is caused to-rock. there- .by carryingits looper at intervals from one In order that the looper may have alongitudinal movement imparted to it by the pitman E, the cross-plate Kof the looper-shaft I is fitted with a pin, 1", that protrudes from itsface through a slot, 8 8 s in the pitmanplate L, so that as the pitmanmoves longitudinally the opposite edges of this slot bear against thepinr and carry the looper-shaft to and fro with the pitman. In orderthat the looper may be in a sufliciently-advanced position to insure itsentrance into the loop of needle-thread, the-slot s s s of the plate Lis formed in two parts, 8 and 8 which are not in intermediate inclinedor curved third part, 8, as represented in Fig. 5. Hence as the pitman Eis carried upward by the movement of the crank-pin the side it ofthepart of the slot 8 bears against the pin 1", moves the looper-shaftforward, and compels the looper to move past the track of the needle inample time to enter into and seize the loop of needle-thread before theneedle is withdrawn from the cloth. When, on the other hand, the pitmanis carried downward the sidet of the part 8 of the slot bears tion ofthe arrow win the drawings, and with a pre'sser-l'oot; but as theseform-no part of my present invention and do not differ materiallyfrolndevices of the usual construction for these purposes it is notdeemed worth while to describe them minutely.

From the relative position and arrangement of the wedge-formedprojections on. the headplate of the looper-shaft and on the pitmanplateit ensues that when the pitman is moved upward by the upward movementofthe crankpin 0 the shifting of the position of the pitman-plate L withreference to the head-plate K causes the looper-shaft I to rock and movethe looper laterally in the direction of the feed, so that when thelooper is moved forward it passes by that side of the needle which istoward the finished seam and enters the loop of needle-thread spread bythe rise of the needle. The parts are then in the positions in whichthey are represented-at Fig. 3. When, on the other hand, the pitman E iscaused to descend hy the rotation of the crankpin, the shifting of theposition ofthe pitman-platc L with reference to the head-plate K causesthe looper-shaft to rock and move the looper in the opposite directionto the feed, thereby moving the looper laterally across the track of theneedle and spreading the loop of second thread carried by the looper, sothat the needle is certain to descend into this loop at its nextdescending move The arts are then in the positions in The my inventionmay be used without the second and the second without the first, ifcases should occur that render such separate use expedient.

The crank-shaft m of the machine represented is arranged torevolve inthe direction of the arrow; but it is obvious thatit may be arranged torevolve in the opposite direction, provided the slot and inclined platesupon the pitman are adapted to this change in the revolution of thecrank-shaft. It is also obvious that the slot may be transposed to theheadplate K and the pin to the pitman-plate, provided the slot beadapted to this change in its location. Having thus described asewing-machineembodying my improvements, What I olailnasmy invention,and desire to secure by Letters Patent, is-- a plates fitted withinclined projections, whereby an intermittent lateral movement isimparted to the looper, substantially as herein set forth.

sooner than it would if moved by the crankpin alone, substantially asherein set forth.

3. The combination of the shaft or stock of the looper with a pitman bymeans of blocks or plates fitted with inclined projections and with apin and cam-slot, whereby the beforedescribed longitudinal and lateralmovements of the looper are derived from the movement of a pitmanoperated by a crank-pin, substantially as herein set forth.

4. The combination of an eye-pointed looper with a hook at its butt,substantially as herein setforth. v In testimony whereof l-have hereuntosubscribed my name.

M. e. WILDER.

Witnesses D. R. WRIGHT, J. B. BISSELL.

